One Word Science explains quantum physics in this video using
cats, Deal or No Deal and Dr Who:
There are three pretty complicated mathematical rules in there.
What you really need to know about quantum mechanics is what those
three rules say.
The rules say that very small things, such as atoms and
electrons, can theoretically behave as both a wave and a particle.
However, if we do an experiment and observe an atom or electron, it
then behaves as only one of those things - either a wave or a
particle. Until we observe the atom, it could be either - we just
don't know!
Remember, a famous physicist said "If you think you understand
quantum mechanics, you don't understand quantum mechanics". The
extremes of physics are always surprising us. What will quantum
mechanics throw up next?
Want to know more about the basics of quantum physics and why
it's important? Have a look at Dr
Quantum explains quantum physics.